The present invention relates generally to an improved method and apparatus for the handling of superimposed stacked receptacles and more specifically to such a method and apparatus for handling of nested superimposed columns of stacked receptacles or containers wherein means are provided for controlling and positioning the carrying bails of the containers at the lower end of the stack so as to permit vertical separation and removal of the lowermost container of the vertical column or stack.
In the packaging of certain commodities, such as, for example, ice cream or the like, carrying containers or receptacles are provided for the convenient packaging of the product, as well as for convenient carrying or handling of the product by the consumer. Containers of this type are normally fabricated from polyethylene, composition board, or the like. These empty containers may be shaped so as to have a generally rectangular cross-section tapering toward a base to permit nesting of the empty containers, with the consequent conservation of storage volume for the empty containers.
Traditionally, these box-like containers have a base, an upper rim, and an outwardly projecting stacking shoulder which is formed along the periphery of the container body and at a location spaced from the upper rim. A generally "U"-shaped carrying bail is secured to opposed side walls of the container at opposed midway points and between the stacking shoulder and the upper rim. When free-hanging, the carrying bail will normally rest against the outer periphery of the body at a downwardly extending or declining angle. When in stacked or nested disposition, these carrying bails frequently interfere with the vertical separation of the bottom or lowermost container of the stack, the carrying bail of the penultimate or higher ordered container in the stack frequently becoming entangled with the upper rim of the lowermost container in the stack. The apparatus of the present invention provides means for controllably positioning the carrying bail of the penultimate and higher ordered containers in a stacked column of containers so as to permit controlled and orderly vertical separation of the lowermost container of the stack.
In my co-pending application, Ser. No. 768,776, filed Feb. 15, 1977, now U.S. Pat. No. 4,082,203 there is described a machine for sequentially depositing frustoconical containers from a stack onto a receiving surface which includes apparatus for ensuring that the bail of the penultimate container in the stack will not interfere with the separation of the lowermost container from the stack. While the machine of the aforereferenced co-pending application is entirely suitable for handling containers having a generally circular cross-section, it has been found to be somewhat unsatisfactory for handling rectangular cross-sectioned containers.
When containers of a rectangular cross-section are stacked, the "U"-shaped bail of a container higher up in the stack will frequently engage the outwardly extending rim of the lowermost container producing an effect known as "daisy chaining". It has been found that the bail orienting device of the aforereferenced application is incapable of obviating the daisy chaining problem in that the simple pivoting of the bail by a leg on the bail orienting mechanism merely serves to clamp a bail more firmly under the rim of the lowermost container.